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Network analysis of Chinese air transport delay propagation

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Chinese Journal of Aeronautics 2017年第2期30卷 491-499页

作者： Massimiliano Zanin seddik Belkoura Zhu Yanbo Innaxis Foundation & Research Institute Jose Ortega y Gasset 20 28006 Madrid Spain Faculdade de Ciencias e Tecnologia Departamento de Engenharia Electrotecnica Universidade Nova de Lisboa Lisboa Portugal Aviation Data Communication Corporation 100083 Beijing China

The Chinese air transport system has witnessed an important evolution in the last decade,with a strong increase in the number of flights operated and a consequent reduction of their *** this contribution,we propose modelling the process of delay propagation by using complex networks,in which nodes are associated to airports,and links between pairs of them are assigned when a delay propagation is *** time series are analysed through the wellknown Granger Causality,which allows detecting if one time series is causing the dynamics observed in a second *** indicate that delays are mostly propagated from small and regional airports,and through flights operated by turbo-prop aircraft,These insights can be used to design strategies for delay propagation dampening,as for instance by including small airports into the system＇s Collaborative Decision Making.

关键词： Air transport Complex networks Delays propagation Functional networksGranger causality

ATM performance measurement in Europe,the US and China

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Chinese Journal of Aeronautics 2017年第2期30卷 479-490页

作者： Andrew Cook seddik Belkoura Massimiliano Zanin Department of Planning and Transport University of Westminster 35 Marylebone Road London NW1 5LS United Kingdom The Innaxis Foundation and Research Institute Jose Ortega y Gasset 20 Madrid 28006 Spain Faculdade de Ciencias e Tecnologia Departamento de Engenharia Electrotecnica Universidade Nova de Lisboa Lisboa 2829-516 Portugal

Air traffic management（ATM） performance and the metrics used in its assessment are investigated for the first time across the three largest ATM world regions：Europe,the US and *** market structure and flow management practices of each region are presented.A wide range of performance data across these three regions is *** topological and performance assessment,the notion of a ＇sufficient＇ sample is often non-intuitive：many metrics may behave non-monotonically as a function of sampling *** and under-developed metrics are identified,and the need for a balance between standardisation and flexibility is *** and cross-sectional metric trade-offs are identified.

关键词： Air traffic management Data Metric Performance Sampling Topology

Epileptic seizure prediction based on EEG spikes detection of ictal-preictal states

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The Journal of Biomedical Research 2020年第3期34卷 162-169页

作者： Itaf Ben Slimen Larbi Boubchir Hassene seddik Centre de Recherche et de Production Research Lab. Ecole Nationale Superieure des Ingenieurs de TunisUniversity of TunisTunis 1008Tunisia Laboratoire d'Informatique Avancee de Saint-Denis Research Lab. University of Paris 8Saint-DenisCedex 93526France

Epileptic seizures are known for their unpredictable ***,recent research provides that the transition to seizure event is not random but the result of evidence ***,a reliable method capable to detect these indications can predict seizures and improve the life quality of epileptic *** periods are generally characterized by epileptiform discharges with different changes including spike rate variation according to the shapes,spikes,and the *** this study,spike rate is used as the indicator to anticipate seizures in electroencephalogram(EEG) *** detection step is used in EEG signal during interictal,preictal,and ictal periods followed by a mean filter to smooth the spike *** maximum spike rate in interictal periods is used as an indicator to predict *** the spike number in the preictal period exceeds the threshold,an alarm is *** the CHB-MIT database,the proposed approach has ensured92% accuracy in seizure prediction for all patients.

关键词： electroencephalogram epilepsy seizure prediction spikes detection

Cooling enhancement of planar-balanced magnetron cathode

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Nuclear Science and Techniques 2017年第8期28卷 69-74页

作者： M'hamed Salhi seddik El Hak Abaidia Brahim Mohamedi Sofiane Laouar Centre de Recherche Nucleaire de Birine B.P. 18017200 Ain-Oussera Algeria Unite de Recherche MPE Faculte des Sciences de l'Ingenieur Universite M'hamed Bougarra de Boumerdes 35000 Boumerdes Algeria

In physical vapor deposition on a magnetron cathode, temperature of sensitive components must be kept under threshold limit, so as to ensure the cathode reliability,the process reproducibility, and the best quality of thin *** can be achieved by an adequate design to enhance the dissipation of heat generated at the cathode. In this paper,temperature distribution and streamlines velocity of the cathode coolant inside a cathode magnetron are analyzed by using CFD solver ANSYS FLUENT in the single-phase method in combination with k–e standards turbulent *** results show that the design is appropriate under the calculation parameters, and for high heat densities some improvements are necessary to enhance heat dissipation and keep temperature under the threshold limit.

关键词：阴极冷却强化磁控平衡平面物理气相沉积 FLUENT 温度分布

Investigation of UV photosensor properties of Al-doped SnO_(2) thin films deposited by sol-gel dip-coating method

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Journal of Semiconductors 2023年第3期44卷 114-123页

作者： Kaour Selma Benkara Salima Bouabida seddik Rechem Djamil Hadjeris Lazhar Laboratory of Materials and Structure of Electromechanical Systems and their Reliability Oum El Bouaghi UniversityAlgeria Faculty of Exact Sciences and Natural and Life Sciences Oum El Bouaghi UniversityAlgeria Electrical Engineering Department Oum El Bouaghi UniversityAlgeria Laboratory of Active Components and Materials Oum El Bouaghi UniversityAlgeria

Transparent conducting aluminum doped tin oxide thin films were prepared by sol-gel dip coating method with differ-ent Al concentrations and characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), UV-Vis spectrophotometry and photoconductivity study. The variation observed in the properties of the measured films agrees with a difference in the film's thickness, which decreases when Al concentration augments. X-ray diffraction analysis reveals that all films are polycrystal-line with tetragonal structure, (110) plane being the strongest diffraction peak. The crystallite size calculated by the Debye Scher-rer’s formula decreases from 11.92 to 8.54 nm when Al concentration increases from 0 to 5 wt.%. AFM images showed grains uni-formly distributed in the deposited films. An average transmittance greater than 80% was measured for the films and an en-ergy gap value of about 3.9 eV was deduced from the optical analysis. Finally, the photosensitivity properties like current-voltage characteristics, ION/IOFF ratio, growth and decay time are studied and reported. Also, we have calculated the trap depth energy using the decay portion of the rise and decay curve photocurrent.

关键词： tin oxide thin films sol-gel UV photodetector photoconductivity trap depth

Coverless Image Steganography Based on Jigsaw Puzzle Image Generation

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Computers, Materials & Continua 2021年第5期67卷 2077-2091页

作者： Al Hussien seddik Saad M.S.Mohamed E.H.Hafez Department of Computer Science Faculty of ScienceMinia UniversityMinya61519Egypt Department of Mathematics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of Mathematics Faculty of ScienceAl-Azher UniversityNasr City11884Egypt Department of Mathematics Faculty of ScienceHelwan UniversityCairoEgypt

Current image steganography methods are working by assigning an image as a cover file then embed the payload within it by modifying its pixels,creating the stego ***,the left traces that are caused by these modifications will make steganalysis algorithms easily detect the hidden payload.A coverless data hiding concept is proposed to solve this *** does not mean that cover is not required,or the payload can be transmitted without a ***,the payload is embedded by cover generation or a secret message mapping between the cover file and the *** this paper,a new coverless image steganography method has been proposed based on the jigsaw puzzle image generation driven by a secret ***,the image is divided into equal rows then further divided into equal columns,creating blocks(i.e.,sub-images).Then,according to secret message bits and a proposed mapping function,each block will have tabs/blanks to get the shape of a puzzle piece creating a fully shaped jigsaw puzzle *** that,the generated jigsaw puzzle image is sent to the *** results and analysis show a good performance in the hiding capacity,security,and robustness compared with existing coverless image steganography methods.

关键词： Coverless information hiding Jigsaw puzzle image image steganography data hiding

EEG epileptic seizure detection and classification based on dual-tree complex wavelet transform and machine learning algorithms

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The Journal of Biomedical Research 2020年第3期34卷 151-161页

作者： Itaf Ben Slimen Larbi Boubchir Zouhair Mbarki Hassene seddik Centre de Recherche et de Production Research Lab. Ecole Nationale Superieure des Ingenieurs de TunisUniversity of TunisTunis 1008Tunisia Laboratoire d^nfbrmatique Avancee de Saint-Denis Research Lab. University of Paris 8Saint-DenisCedex 93526France

The visual analysis of common neurological disorders such as epileptic seizures in electroencephalography(EEG) is an oversensitive operation and prone to errors,which has motivated the researchers to develop effective automated seizure detection *** paper proposes a robust automatic seizure detection method that can establish a veritable diagnosis of these *** proposed method consists of three steps:(i) remove artifact from EEG data using Savitzky-Golay filter and multi-scale principal component analysis(MSPCA),(ii) extract features from EEG signals using signal decomposition representations based on empirical mode decomposition(EMD),discrete wavelet transform(DWT),and dual-tree complex wavelet transform(DTCWT) allowing to overcome the non-linearity and non-stationary of EEG signals,and(iii) allocate the feature vector to the relevant class(i.e.,seizure class "ictal" or free seizure class "interictal") using machine learning techniques such as support vector machine(SVM),k-nearest neighbor(k-NN),and linear discriminant analysis(LDA).The experimental results were based on two EEG datasets generated from the CHB-MIT database with and without overlapping *** results obtained have shown the effectiveness of the proposed method that allows achieving a higher classification accuracy rate up to 100% and also outperforms similar state-of-the-art methods.

关键词： electroencephalography epileptic seizure detection feature extraction dual-tree complex wavelet transform machine learning

Hacking Anti-Shoplifting System to Hide Data within Clothes

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Computers, Materials & Continua 2021年第4期67卷 659-674页

作者： Al Hussien seddik Saad E.H.Hafez Zubair Ahmad Department of Computer Science Faculty of ScienceMinia UniversityAl-Minya61519Egypt Department of Mathematics Faculty of ScienceHelwan UniversityCairoEgypt Department of Statistics Yazd UniversityYazdIran

Steganography has been used to prevent unauthorized access to private information during *** is the scheme of securing sensitive information by concealing it within carriers such as digital images,videos,audio,or *** steganography methods are working by assigning a cover le then embed the payload within it by making some modications,creating the ***,the left traces that are caused by these modications will make steganalysis algorithms easily detect the hidden *** to solve this issue,a novel,highly robust steganography method based on hacking anti-shoplifting systems has proposed to hide data within *** anti-Shoplifting system is an anti-theft security system that protects goods and products,leaving the store in an illegal way(i.e.,without paying for them).The proposed method works by modifying the default anti-shoplifting system by changing its built-in soft RFID(radio-frequency identication)tags sewn in clothes into NFC(Near Field Communication)*** NFC tags are smart tags that can communicate with NFC-Enabled smart-phones using NDEF(NFC Data Exchange Format).NDEF is one of the advancements added to RFID technology by NFC,which allows the data *** NDEF message has one/more NDEF records that contain record type,a unique ID,a length,and a payload of data that contains the secret message content that can be any type of data that ts in a byte *** on NDEF and NFC-enabled smart-phones,the proposed method will take the secret message from the sender,make use of his NFC-enabled smart-phone to communicate with the NFC tag,then hide the secret message within the NDEF’s payload of the NFC tag stuck in ***,to evaluate the proposed method,it has been compared with default(digital)steganography weak *** as time,lockable,robustness,attacks,capacity,and a few more *** results and comparisons showed that the proposed method is more efcient than default(digital)steganography and

关键词： Near-eld communication radio-frequency identication Steganography data hiding tags

Optimized sequential therapy vs 10- and 14-d concomitant therapy for eradicating Helicobacter pylori: A randomized clinical trial

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World Journal of Gastroenterology 2024年第6期30卷 556-564页

作者： Hassan seddik Jihane Benass Sanaa Berrag Asmae Sair Reda Berraida Hanae Boutallaka Department of Gastroenterology II Mohammed V Military Teaching Hospital of RabatRabat 10100Morocco Department of Gastroenterology Mohammed V University in RabatRabat 10100Morocco Department of Gastroenterology I Mohammed V Military Teaching Hospital of RabatRabat 10100Morocco

BACKGROUND A cure for Helicobacter pylori(***)remains a problem of global *** prevalence of antimicrobial resistance is widely rising and becoming a challenging issue *** sequential therapy seems to be one of the most attractive strategies in terms of efficacy,tolerability and *** most common sequential therapy consists of a dual therapy[proton-pump inhibitors(PPIs)and amoxicillin]for the first period(5 to 7 d),followed by a triple therapy for the second period(PPI,clarithromycin and metronidazole).PPIs play a key role in maintaining a gastric pH at a level that allows an optimal efficacy of antibiotics,hence the idea of using new generation *** open-label prospective study randomized 328 patients with confirmed *** infection into three groups(1:1:1):The first group received quadruple therapy consisting of twice-daily(bid)omeprazole 20 mg,amoxicillin 1 g,clarith-romycin 500 mg and metronidazole 500 mg for 10 d(QT-10),the second group received a 14 d quadruple therapy following the same regimen(QT-14),and the third group received an optimized sequential therapy consisting of bid rabe-prazole 20 mg plus amoxicillin 1 g for 7 d,followed by bid rabeprazole 20 mg,clarithromycin 500 mg and metronidazole 500 mg for the next 7 d(OST-14).AEs were recorded throughout the study,and the *** eradication rate was determined 4 to 6 wk after the end of treatment,using the 13C urea breath *** In the intention-to-treat and per-protocol analysis,the eradication rate was higher in the OST-14 group compared to the QT-10 group:(93.5%,85.5%P=0.04)and(96.2%,89.5%P=0.03)***,there was no statist-ically significant difference in eradication rates between the OST-14 and QT-14 groups:(93.5%,91.8%P=0.34)and(96.2%,94.4%P=0.35),*** overall incidence of AEs was significantly lower in the OST-14 group(P=0.01).Furthermore,OST-14 was the most cost-effective among the three *** The optimized 14-

关键词： Helicobacter pylori Quadruple therapy Sequential Proton-pump inhibitor Optimization